Science & Technology, Australia (Commonwealth Union) – A novel laboratory-created substance replicates human tissue, potentially reducing or substituting the need for animal-derived materials in biomedical research.
Researchers at University of New South Wales (UNSW) have developed a pioneering material poised to revolutionize the cultivation of human tissue in laboratories and its application in medical procedures.
This newfound substance belongs to the hydrogel family, which constitutes the foundational element of the pliable materials found in all living organisms, such as animal cartilage and plant seaweed. Hydrogels possess qualities that render them invaluable in biomedical research, as they can simulate human tissue, enabling cell growth within a controlled laboratory setting.
The fundamental structure of hydrogels is deceptively simple. These materials are composed of short peptides, which are the basic building blocks of proteins. This simplicity contributes to their versatility, as they can be engineered to possess specific properties, such as elasticity, porosity, and biocompatibility.
Although there are human-made hydrogels already in use across various consumer products, from food and cosmetics to contact lenses and absorbent materials, they have more recently found application in medical research to close wounds and substitute damaged tissue. However, these synthetic hydrogels often fall short in recreating the intricate properties of authentic human tissue.
In a research paper published in Nature Communications, UNSW scientists describe a newly devised laboratory-manufactured hydrogel that closely mimics natural tissue, exhibiting surprising attributes with far-reaching implications for medical, food, and manufacturing technology.
Associate Professor Kris Kilian, affiliated with UNSW’s School of Materials Science & Engineering and School of Chemistry, notes that this hydrogel material is composed of simple, short peptides, the fundamental building blocks of proteins.
Associate Professor Kilian pointed out that the material is bioactive that refers to the encapsulation of cells acting like there residing within a natural tissue.
“At the same time, the material is antimicrobial, meaning that it will prevent bacterial infections. This combination lands it in the sweet spot for materials that might be useful in medicine. The material is also self-healing, which means that it will reform after being squished, fractured, or after being expelled from a syringe. This makes it ideal for 3D bioprinting, or as an injectable material for medicine.”
Ashley Nguyen, a doctoral candidate at UNSW School of Chemistry and the primary author of the paper, made a groundbreaking discovery while working on her research during the COVID-19 lockdown. Her discovery emerged from computer simulations aimed at identifying molecules capable of self-assembly, a process where these molecules spontaneously arrange themselves without human intervention. During this research, Ms. Nguyen stumbled upon a fascinating concept known as “tryptophan zippers.” These are concise chains of amino acids that feature multiple tryptophans, acting like a zipper to facilitate self-assembly. These unique sequences have been aptly named “Trpzip.”
Ms. Nguyen expressed her excitement at the prospect of identifying a distinctive peptide sequence through computational simulations that had the potential to form a hydrogel.
“After we returned to the lab, I synthesised the top candidate and was thrilled to see it actually form a gel.”
Ms. Nguyen believes that the revelation of this hydrogel holds the promise of serving as an ethicaly sound substitute for the commonly employed natural materials.
“Natural hydrogels are used all over in society—from food processing to cosmetics—but require harvest from animals which poses ethical concerns,” said Ms. Nguyen.
To assess the practicality of Trpzip in biomedical research, Associate Professor Kilian’s team collaborated with Dr. Shafagh Waters, a researcher in the School of Biomedical Sciences at UNSW. Dr. Waters traditionally employs Matrigel, a hydrogel derived from mouse tumors, for cultivating patient tissue in her research.
They hope to move forward to carry out further tests by partnering with industry.
